The use of positive airway pressure (PAP) for the treatment of sleep disordered breathing (SDB), such as obstructive sleep apnea (OSA), was disclosed in U.S. Pat. No. 4,944,310. Treatment using PAP, which may be continuous PAP, or CPAP, involves the use of a patient interface which is sealingly attached to the patient's face for the provision of the flow of breathable gas. PAP treatment involving the use of a patient interface that is sealingly attached to the wearer's face may be referred to as closed PAP.
Mild or moderate cases of SDB may not be suitable for treatment using closed PAP methods. For example, patients who experience mild sleep apnea, or who may snore, may not gain a significant benefit from the use of closed PAP treatment. In addition, such patients may tend to resist treatment as closed PAP treatment methods generally are obtrusive.
U.S. Pat. No. 7,080,645 discloses an anti-snoring device including a compressor and a nasal air cannula. An air compressor blows air through the nasal cannula into the nose of a sleeping person. The nasal air cannula may, or may not, form a tight seal with the sleeping person's nostrils. If no seal is formed, a throttle valve is provided between the air compressor for flow regulation. If a seal is formed, a bypass valve is provided to allow the sleeping person to exhale.
Because of the small diameter of the nasal cannula, the pressure drop is significant and the compressor must be able to generate excess pressure from 100 to 1,000 mbars relative to ambient. In order to reduce, or prevent, the noise generated by the air compressor from reaching the sleeping person, the air compressor may be fitted with acoustic insulation. A turbine regulator may be provided to the air compressor so that the compressor turbine is able to run at the lowest possible angular speed. The air compressor may also be located in an adjacent room, which may prevent the person from operating the turbine regulator.
The nasal air cannula of U.S. Pat. No. 7,080,645 comprises two tubes running rearward over the ears of the sleeping person. The noise generated by the flow through the cannula may be distracting and disrupt the person's sleep cycle.
For patients that require a higher prescribed pressure for treatment of OSD, a patient interface, e.g. a mask, that forms a seal with the patient's airways may be required. However, the patient may find adapting to current interfaces difficult. For example, the patient may have difficulty sleeping in a familiar, comfortable position once the mask, including the headgear and air delivery hose, are fitted to the patient to provide the required seal. Although the mask is capable of providing a seal and the prescribed pressure, the patient may be reluctant to use the mask due to the problem of sleeping comfortably while wearing the mask. This may result in the patient abandoning the treatment.